Foldable boat



- val May 8, 1962 Filed March 21, 1960 B. F. RANDRUP FOLDABLE BOAT 3 Sheets-Sheet 1 INVENTOR. BENJAMIN F RANDRUP BY 61,4, mil. wm/

ATTORNEYS y 1962 B. F. RANDRUP 3,032,784

FOLDABLEBOAT Filed March 21, 1960 3 Sheets-Sheet 5 IN VEN TOR. BENJAMIN RANDRUP A T TO/PNEYS 3,032,784 FOLDABLE BOAT Benjamin F. Randrup, 423 Roberta Ave., Pleasant Hill, Calif. Filed Mar. 21, 1960, Ser. No. 16,394 15 Claims. (Cl. 9-2) This invention relates to improvements in foldable boats. Foldable boats of the general type herein described have been previously disclosed in Letters Patent No. 2,504,225, issued April 18, 1950. Such boats are intended to be folded to a relatively compact flat condition for storing or transporting and yet are adapted to be unfolded, in a relatively short time, to a set-up position for use by fishermen, campers, sportsmen and the like.

One of the primary problems in prior foldable boat construction of this type wherein panels are flexibly joined longitudinally of the boat is the prevention of leakage in the flexible joints between such panels which form the hull. Another problem that has occurred in such prior boat construction is that of providing sufficiently rugged hull members and bracing therefor to withstand the severe usage to which such boats are subjected in addition to carrying heavy loads, especially outboard motors and other boat accessories.

It is therefore a main object of this invention to provide improvements in a foldable boat which overcome the deficiencies and disadvantages of prior art construction.

Another object of thi invention is the provision of a foldable boat which may be easily and readily unfolded from a compact storage condition into a set-up hull having improved handling characteristics in the water.

It is a further object of this invention to provide a foldable boat which, when in unfolded or set-up condition is sufiiciently strong and rugged to withstand substantial loads without danger of collapsing or capsizing.

Still another object of this invention is the provision of a foldable boat which may be set up to form a completely watertight hull.

Other objects and advantages will become apparent from the following description taken in connection with the accompanying drawings in which:

FIG. 1 is a top plan view of the foldable boat of this invention in unfolded or set-up condition;

FIG. 2 is a perspective view of the boat of FIG. 1;

FIG. 3 is a greatly enlarged sectional view as seen from line 3-3 of FIG. 1;

FIG. 4 is a bottom plan view of the boat of FIG. 1;

FIG. 5 is an enlarged sectional view as seen from line 5-5 of FIG. 1;

FIG. 6 is an enlarged sectional view as seen from line 66 of FIG. 2;

FIGS. 7 and 8 are enlarged sectional views as seen from lines 77 and 8--3, respectively, of FIG. 4;

FIG. 9 is a greatly enlarged sectional view as seen from line 99 of FIG. 2;

FIGS. 10, 11, 13 and 14 are enlarged perspective views of a corner of the stern of the boat of FIG. 2, illustrating in progressive steps the formation of the watertight corner joint;

FIG. 12 is a sectional view as seen from line 12-- 12 of FIG. 11, and,

FIG. 15 is a greatly enlarged sectional view as seen from line 1515 of FIG. 2.

In detail, referring to FIGS. 1 and 2, the boat of this invention generally comprises a pair of elongated bottom panels 1, 2 flexibly or hingedly connected along their adjacent longitudinal edges at the longitudinal center line of the boat. A pair of elongated side panels 3, 4 are respectively flexibly or hingedly connected along their lonnited States Patent 0 gitudinally extending lower edges to the opposed outer edges of panels 1 and 2. The forward ends of panels 1 and 2 merge to form a pointed bow, generally designated 5, and a transom panel 6 connected to the rear end edges of panels 1, 2, 3 and 4 encloses the stern of the boat. One or more thwarts, generally designated 7, extend transversely between the side panels 3, 4 for holding said panels inunfolded or set-up condition.

When the boat is in such set-up condition the bottom panels 1, 2 extend generally horizontally from the stem at transom panel 6 to the bow 5 of the boat. Said bottom panels are generally rectangular in shape but are preferably somewhat wider amidships than at their rear ends at the stern and are formed to pointed forward ends at the how 5. Said bottom panels are preferably made from flat sheet material, such as marine plywood or hardboard surfaced plywood, and are bent to assume a convex shape at their forward end portions. Bottom panels 1, 2 are also preferably oppositely upwardly and outwardly inclined throughout their lengths and have progressively greater inclination toward their forward ends (FIGS. 2, 3, 8).

Side panels 3, 4 are generally triangular in shape and are preferably made from the same material as bottom panels 2. Said side panels extend from transom 6 at the stern of the boat to points short of the pointed how 5 and form the generally upright .sides of the boat. Side panels 3, 4 are convexly outwardly curved and oppositely upwardly and outwardly inclined near their forward ends so as to merge with bottom panels 1, 2 in providing a hydro-dynamically proper hull. The upper free edges of said side panels and of the pointed forward ends of bottom panels 1, 2 form the gunwales of the boat.

Said upper free edges of side panels 3, 4 may be protected by a gunwale member 10 (FIGS. 1, 2, 15) in the form of an elongated member having an inverted, generally U-shaped cross section. Member 10 is preferably formed from a resilient material and may have its free edge marginal portions 11 turned inwardly and upwardly into parallel, spaced relationship for receiving therebetween the upper free edge of side panels 3, 4 (FIG. 15). Member 10 may be made of sufiiciently resilient material so that the edge portions 11, and particularly oppositely inwardly projecting sharp ridges 12 on said edge portions, are held by the resiliency of member 10 in frictional and gouging engagement with the surfaces of panels 3, 4 for holding member 10 in place against upward withdrawal. Outwardly opening notches may be provided in said side panels to receive inwardly directed sharp ridges 12 (FIG. 15). Screws 13, projecting through portions 11 and side panels 3, 4 may serve as optional means to hold gunwale members 10 in place extending along the upper free edges of said side panels. The gunwale members 10 may extend a few inches rearwardly of the transom 6 to serve as handles and protective bumpers (FIGS. 1, 2).

Extending along the longitudinal center line of the hull of the boat between bottom panels 1 and 2 is a keel construction, generally designated 14 (FIGS. 1, 4, 7). Said keel construction includes the means which flexibly or hingedly connect the adjacent longitudinal side edges of bottom panels 1 and 2 in the form of an elongated strip 15 (FIG. 7) of flexible, waterproof material, such as rubberized fabric or the like. Nylon fabric impregnated with neoprene is desirable for this use because of its impregnability to gasoline and oil. It will be noted from FIG. 7 that the longitudinal edges of bottom panels 1, 2 are protected and reinforced by elongated angle members 16, one leg 17 of each of which extends along the inwardly directed edge of its respective bottom panel and the other leg 18 of which overlies the upper surface of said bottom panel adjacent said edge.

Flexible strip 15 extends across the intervening space between panels 1 and 2 and has its longitudinal side edges folded inwardly and under legs 18 of angle members 16, whereby strip 15 may be secured in watertight relation to panels 1 and 2 by a plurality of rivets 19 extending through the overfolded portions of flexible strip 15, legs 18, and bottom panels 1 and 2. In addition, a waterproof adhesive, such as solvent activated, may be applied to the turned under edges of flexible strip 15 to assure the formation of a watertight joint. Strip 15 is connected in this manner to bottom panels 1 and 2 along the entire length of their adjacent longitudinal side edges from the bow of the boat to its stern and thereby serves to connect said bottom panels for folding one on the other.

Included in the keel construction 14 of the foldable boat of this invention is an elongated keel member comprising an inverted channel 20 (FIGS. 2, 7) having a generally horizontally extending central web 21, a pair of downwardly depending legs 22, and a pair of flanges 23 extending oppositely outwardly from the lower edges of legs 22. Channel 20 is disposed between the longitudinal side edges of bottom panels 1 and 2 with web 21 positioned upwardly of the lower surfaces of said panels when the same are in unfolded condition (FIG. 7). In this position the marginal edge portions of panels 1 and 2 are received in the outwardly and upwardly opening angles formed by legs 22 and flanges 23 and flexible strip 15 overlies the upper surface of web 21.

An elongated batten 24, of wood or the like, extends along the keel in overlying relation to the central portion of strip 15 and is secured in place by a plurality of bolts or rivets 25 extending through said batten, strip 15, and the web 21 of channel 26. Batten 24 serves both to protect the upper surface of flexible strip 15 in the interior of the boat and to connect channel 20 to strip 15 and thence to bottom panels 1 and 2.

This keel construction functions in the manner of hinge means to connect bottom panels 1 and 2 for folding on each other to a collapsed position as indicated by dotdash lines 26 in FIG. 7. When panels 1 and 2 are in the unfolded condition, indicated in solid lines in FIG. 7, channel 20 and flexible strip 15 function to hold the inner side edges of .said bottom panels in spaced relation and span the space so formed between the panel edges upwardly of the lower surfaces of said panels to provide an unobstructed downwardly opening groove extending along the longitudinal center line of the boat. It will be noted in FIGS. 2 and 4 that channel 20 extends rear- Wardly from midship to stern and opens outwardly of the stern to provide such downwardly opening groove through a substantial length of the keel of the boat.

The provision of a keel on a boat is for the purposes of increasing the maneuverability and handling characteristics thereof. Conventional keels are usually in the form of a downwardly projecting ridge along the bottom of the boat provivding outwardly facing generally vertical surfaces for preventing sidewise slippage of the hull in the water. The improved, so-called inverted keel of this invention has several substantial advantages over conventional keels, while at the same time providing the generally vertical surfaces of legs 22 of channel 20 for the above mentioned purpose. Since no portion of the keel construction herein described (with the slight exception of the very thin flanges 23) projects below the bottom panels of the hull, the draft of the herein described boat may be considerably shallower than a boat with a conventional projecting 'keel.

The conventional, projecting keel is subject to excessive abuse whenever a boat is pulled ashore. The entire weight of such boat usually rests upon a very small area on the bottom of the keel. This has resulted in fraying or breakage of the usual wood member. In this invention the portion of the boat resting upon the ground is the relatively flat metal flanges 23, thus eliminating the disadvantages of the conventional keel.

Furthermore, the boat of this invention may be more safely used with an outboard motor than conventional boats. Normally the transom depth (from the top of the transom on which the outboard motor is mounted to the bottom of the keel) must be set to accommodate the freeboard of the motor (the standard dimension from the motor mount to the motors cavitation plate) so that the propeller will be at the correct depth below the bottom of the boat. In the boat of this invention the depth of the transom panel may be made sufficient to provide a safe freeboard for the boat (that is, the distance from the waterline to the upper edge or gunwale of the transom panel) to prevent backwash into the boat and still accommodate a standard outboard motor mounted on the transom in a conventional manner.

In the foldable boat of this invention each side panel 3, 4 is hingedly connected to its respective bottom panel 1, 2 along the lower longitudinal edge of the side panel and the outer longitudinal edge of the bottom panel by means such as an elongated strip of flexible material 30 (FIG. 12). These strips 30 extend along the junctures between the side panels and bottom panels or the chines of the hull for the entire length thereof (FIGS. 1, 2). Each said strip 30 is folded to a generally G-shaped or U-shaped cross section and has its free marginal edges secured in watertight relation to the respective adjacent edges of the associated side and bottom panel. One such securing means, which also provides protection for the panel edges, is shown in FIGS. 12, 13 as angle member 31. One leg of each angle member 31 may overlie a marginal edge of strip 31 while the other leg depends alongside the free edge of the panel to which it is connected. Preferably, angle members 31 are secured by rivets 32 to the panels in this position and a waterproof adhesive may be applied, if desired, to insure a secure and watertight joint. It will be noted that the manner of connection of flexible strip 30 to the side and bottom panels is substantially similar to that previously described for connection of strip 15 to the bottom panels.

This method of hingedly or flexibly connecting the side and bottom panels not only forms a watertight joint at the chines of the boat, but also permits each side panel to fold on its adjacent bottom panel as indicated by dotdash lines 33 in FIG. 12. When the boat is in unfolded or set-up condition, the lower edge of each side panel normally rests on the upper surface of the adjacent bottom panel adjacent the outer edge thereof. Since both these edges are protected by the preferably metallic angle members 31, damaging contact between the panel edges and/or with the flexible strip 30 is prevented.

The adjacent edges of panels 1 and 2, panels 1 and 3, and panels 2 and 4 are slightly convexly curved so that when said panels are in the unfolded condition the central portions thereof tend to spring outwardly. The end portions of said panels, by the same action, tend to separate from each other. These tendencies of the panels to spring outwardly at their central positions and to spring apart at their ends would tend to put the flexible strips 15 and 30 under tension.

Such tension may be relieved by connecting the bow ends of panels 1 and 2, 1 and 3, and 2 and 4 by additional hinge means in the form of conventional metal butt hinges for holding said bow ends together with flexible strips 15 and 30 in a relaxed condition. At the stern end angle clips 28 (FIGS. 2, 4, 13, 14) riveted to the outer edges of panels 1 and 2 with a leg of each projecting upwardly along the outside of panels 3, 4, respectively, serve to hold the stern ends of panels 1 and 3 and 2 and 4 together with the ends of strips 30 relaxed. The construction of transom 6 (to be described) is such that it holds the adjacent stern edges of bottom panels 1 and 2 together without tensioning the stern end of strip 15.

The central portions of the lower edges of panels 3 and 4 are prevented from springing outwardly with respect to the outer edges of panels 1 and 2, respectively, by angle members 29 (FIG. 12) which are secured to panels 1 and 2 with a leg of each projecting upwardly along the outside of panels 3 and 4. Angle members 29 thereby hold panels 3 and 4 in their proper relation to panels 1 and 2 in which strips 30 are not under tension and no portions of the panels are in engagement with the strips 30.

The transom panel 6 which encloses the stern of the boat in this invention is preferably formed from a plurality of separable panels 34, 35, 36 (FIG. 5 These panels may be formed from the same type of material as side panels 3, 4 and bottom panels 1, 2. The two inner panels 34, 35 overlie one another, when in the set-up condition, and a flexible rear end member 37 overlies the outer or rear surface of panel 35. Member 37 may be formed from the sam type of rubberized fabric material as flexible strips 15 and 30 and has its bottom and side peripheral edges secured in watertight relation to the rear end edges of the bottom panels 1, 2 and side panels 3, 4 respectively. Outer protective panel 36 extends across the outer surface of flexible member 37.

The rear end panels 34, 35 are respectively swingably connected along their generally vertical side edges to side panels 3, 4, as by hinges 38 (FIG. 6) for folding thereon. The side panels may be provided with vertical reinforcing strips 33 at the line of connection of the elongated hinges 38 and each end panel 34, 35 is preferably provided with a vertical strip at the hinge 38 providing an abutment shoulder 40. Panels 34, 35 do not extend completely across the stern of the boat, but each extends from the side panel to which it is hingedly connected into engagement with the shoulder strip 40 on the other end panel.

When unfolding and setting up the boat, the free end of rear panel 35 is first brought into engagement with the shoulder strip 45 (not shown) on the panel 34 and said latter panel is then swung rearwardly to a position against rear panel 35 and with the free edge of panel 34 in engagement with the shoulder strip 40 attached to panel 35. The horizontal extent of flexible member 37 is such that it is drawn taut against the outer surface of panel 35 by this interengagement of the panels.

Each panel 34, 35 is also provided along one-half of its lower edge with a projecting lip 41 (FIG. 5) on which rests the corresponding half of the lower edge of the other of said panels. The central portion of the lower edges of panels 34, 35 are cut away to receive the outwardly projecting keel construction 14 but the remaining portions of such lower edges, including the oppositely projecting lips 41 of panels 34, 35, engage bottom panels 1, 2 and hold them in the slightly inclined relation shown in FIG. 2.

The connection of the peripheral edges of flexible rear end member 37 to the rear end edges of bottom panels 1, 2 and side panels 3, 4 may be similar to that employed for connection of flexible strips 15 and 30. That is, angle members 42 (FIG. 6) may be riveted to side panels 3, 4 with one leg of the angle overlying the folded under peripheral side edge portion of flexible member 37 and with the other leg of the angle member extending across the rearwardly directed edge of the respective side panel. A pair of similar angle members 43, each approximately as long as the width of the rear end edge of a bottom panel are similarly riveted thereto for securing the under folded bottom peripheral edge of flexible member 37 to said bottom panels. As in the case of flexible strips 15 and 30, an adhesive compound may be spread on the connections of member 37 to assure watertight joints.

Reverse angle members 44 (FIG. 6) may be secured back to back with angles 42 on the rear edges of side panels 3, 4 with the legs of angles 44 directed oppositely inwardly, thereby forming channels for receiving the opposed vertical edges of separate, outer rear panel 36. Panel 36, in this position overlying the rear side of flexible member 37, serves to protect the latter as Well as strengthening the entire transom panel 6. Panel 36 may also be provided with a forwardly extending lip 45 (FIG. 5) along its upper edge for projecting over the upper edges of flexible member 37 and inner panels 34, 35.

When set up the component panels comprising transom panels 6 are preferably clamped together by means such as a through bolt 46. The transom panel thus described is Watertight and strong enough for normal usage, but it is advisable to provide a transom brace, generally designated 47, where an outboard motor is intended to be mounted on said transom panel.

Brace 47 is preferably fabricated from angle iron or channel iron and comprises an elongated base member 48 (FIG. 5) secured to the keel '14, as by bolting through channel member 20 and batten 24. An upright member 49 is swingably connected by pivot 50 to the rear end of base member 48 and is thereby swingable from a collapsed position overlying said base member to a raised position projecting upwardly alongside the inner surface of rear end panel 34.

An inclined member 51, swingably connected to base member 48 at a point forwardly of its rear end by pivot 52 is similarly swingable from a collapsed position extending along keel 14 to a bracing position with its upper end in engagement with the upper end portion of member 49. A transversely extending bearing plate 53 may extend over the upper central portion of inner end panel 34 to reinforce the transom panel against the clamping action of the outboard motor mount. Plate 53 may be secured either to panel 34 or to upright member 49, and through bolt 46 extends through said bearing plate and the upper, engaging ends of brace members 49 and 51. A tubular nut 54 with a handle may be threadedly received on the inner end of bolt 46 for clamping the brace member, bearing plate and rear end panels together. An outer reinforcing plate 55 on the outer surface of panel 36 may be provided if desired.

In prior art folding boats the most diflicult portions in which to provide watertight folding joints have been the corners where three panels in different plane-s meet. Such corner joints exist at the junctures between two longitudinal panels, one of which is a bottom panel, and the rear end or transom panel. In the boat of this invention improvements have been made in rendering the joints watertight at the rear corner-s of the stern and where the keel intersects the stern.

At theselocations the flexible rear end member 37 is provided with ear portions 56 (FIGS. 9, 13) which project outwardly from the remainder of the peripheral edge of said flexible member. At each of these same locations tail portions 57 are provided in continuation of and extending rearwardly from the respective flexible strips 15 and 30 (FIGS. 9, 10, 11 and 13). The ends of the strips 15 and 30 are joined in watertight relation to flexible rear end member 37 and by rolling ear portions 56 and the respective tail portions 57 together, with ear portions 56 on the inside of the rolls thus formed.

As previously described, each of the flexible strips 15 and 30 have an inverted, generally U-shaped cross section when the boat is in the set-up condition (FIGS. 7, 12). In order to provide the relatively flat tail portions which are to be rolled with the ear portions 56, each of the flexible strips 15, 36 must first be folded forwardly on itself and then rearwardly over the previously folded portion While the extending tail portion 57 is flattened from its U- shaped cross section. FIGS. 10, 11, 13 and 14 illustrate the steps which are performed in providing the improved watertight corner joint of this invention, and such steps are also illustrative of the formation of the watertight joint at the intersection of keel strip 15 and flexible rear end member 37.

By folding the flexible strip 30 (or 15 as the case may be) forwardly on itself to form a fold 58 (FIG. 10) and then folding it rearwardly over said fold, the tail portion 57 assumes a shape that is somewhat inverted (FIG. 11)

7 from that which it assumes when connected between the associated panels (FIG. 12). It is advisable to spread a suitable adhesive compound on the fiexible strip at this oyerfolded portion and between said strip and the associated panels. By this construction the connected panels, such as bottom panel 1 and side panel 3 illustrated in FIG. 11, may be folded on each other without disturbing the watertight joint formed by flexible strip 30 to fold 58.

Strips 59 of sponge rubber or the like with adhesive on beth sides are placed with their pointed ends under fold 50 and extending transversely away from strip 30 along the rear edges of panels 1, 3 (or 2, 4). The respective ear portion 56 is then placed in overlying relationship to the rearwardly projecting tail portion 57 of member 37 and the two are enfolded or rolled together forwardly toward flexible member 37 with tail portion 57 on the outside of the roll thus formed (FIG. 13). The roll is then flattened on underlying told 58 and clamped or secured to the rear edges of the panels 1, 3 by the overlying legs of the angle members 42, 43 (FIG. 14) secured to said panels by rivets 60. It will be noted that the ends of angle members 42, 43 overlie the lateral edge portions of ear portion 56 and tail portion 57 in the rolled joint fold 58, and strips 59. This construction coupled with the preferable addition of an adhesive compound both to the interior of the rolled portions as well as between the roll strips 59, and the adjacent panels provides a completely watertight corner joint, especially since strips 59 are compressed by angle members 42, 43 and act as fillers between fold 58 and the adjacent panels.

Such joint does not interfere in any way with the folding of the associated panels one on the other since the central portion 61 (FIG. 14) of the rolled ear and tail portions is-flexible and may be folded in the same manner asthe remainder of the flexible strip 30 (or 15).

FIG. 9 -illustrates the rolled portions 56, 57 at the juncture of the keel with the stern and the reverse fold 58 which provides the relatively flat tail portion '57. The roll formed by enfolding portions 56, 57 on flexible strip 15 and flexible member 37 is secured in watertight relation to the rear end edges of bottom panels 1 and 2 in a similar manner by clamping the lateral edge portions of said roll under the ends of angle members 43. Filler strips, such as 58, may also be incorporated under the edge portions of such roll. This joint is similarly provided with a flexible central portion so that the bottom panels 1, 2 may befolded on each other.

In the case of each such joint, since the flexible strip is secured in watertight relation to the panels which it connects up to the point where the flexible rear end member 37 is so secured to the panels, the joining or enfolding of the strip and the flexible rear end member into watertight relation forms a completely watertight, yet foldable connection.

The keel construction previously described is somewhat modified near the forward end 01' bow of the boat. It is not necessary to provide the downwardly opening channel near the bow since the forward portion of the boat is often out of the water especially at increased speeds. The batten 24- and flexible strip 15, connected in the manner described to bottom panels 1, 2, preferably extend forwardly all the way to the pointed how as shown in FIGS. 3, 8. Channel 20, however, may terminate rearwardly of bow 5 and in its place an elongated spacer member 62 (FIG. 3) extends along the longitudinal center line of the boat under flexible strip 15. A flat strip 63, preferably of metal or other rigid material, extends along the other surface of spacer member 62 from the end of channel 20 to the upper forward corners of panels 1, 2 at bow 5 (FIG. 4). The rear end of strip 63 may be riveted to the forward end of channel 20 (FIG. 4) and the remainder of said flat strip is secured together with spacer '63, the central portion 'of flexible strip 15, and batten 24 by a plurality of spaced bolts 64 (FIG. 8) or 8 rivets. The spacer 62 may be individual blocks positioned at the bolts only.

Along the forward, upwardly curved portion of the how an elongated, transversely curved cap strip '65 (FIGS. 3, 4, 8) is secured in overlying spaced relation to strip 63 by belts 64 and tubular spacers 69. The upwardly and rearwardly inclined outer edges of cap strip 65 extendover and thereby protect the oppositely inwardly directed longitudinal edges of panels 1 and 2. A bow cap 66 (FIGS. 1-3) may be provided extending over the forward upper end of strip 63 and spacer 62. Bow cap 616 may be secured to strip 65, and obviously, sufficient clearance must be provided for the edges of bottom panels 1 and 2 for folding the same together as indicated by dot-dash lines 67 in FIG. 8.

in order to prevent undue spreading of the upper free edges of bottom panels 1 and 2 at bow 5 by the thwarts 7, a generally triangular, flexible member 68 (FIGS. l-3) is permanently secured along two of its peripheral edges to said upper free edges of said bottom panels. It is not necessary that deck member 68 extend rearwardly past the juncture of side panels 3 and 4 with bottom panels 1 and 2. The transverse extent of deck member 68 is such that it is pulled taut between the upper edges of panels 1 and 2 when the boat is in the unfolded condition and thereby serves to hold the upper edges or gun wales of the panels from undue spreading.

Preferably, deck member 68 is formed from a waterproof material such as rubber impregnated fabric and tubular gunw-ale members 70, similar to member 16 may be secured over the upwardly directed free edges of bottom panels 1 and 2 adjacent the connection of deck member 68 thereto. If preferred, gunwale members 70 may be formed of a rigid material and provided with inwardly directed portions 71 (FIG. 1) connected to the comers of deck member 68 at its rear edge.

In order to hold the bottom and side panels in the proper shape for forming the hull of the boat, as described, this invention provides one or more thwarts, generally designated 7 (FIGS. 1, 2 and 5) which engage and spread said panels in the set-up condition of the boat. Each of said thwarts extends transversely of the boat amidships between side panels 3 and 4 and preferably comprises an elongated seat member 72 which has its opposed ends received in oppositely inwardly opening sockets 73 secured to or formed in said sidewalls. Two or three of such seat members may be provided and the transverse extent thereof is such as to spread the side panels 3, 4- again'st their inherent resiliency to form the oppositely outwardly curving sides of the boat (FIGS.

1, 4). Seat members '72 are preferably independent and separable from the remainder of the boat and may be inserted in the sockets 73 by springing side panels 3, 4 outwardly against their own resilience. Obviously, the resiliency of said side panels will serve to retain the ends of seat members 72 in sockets 73.

Hin-gedly cone'cted to each seat member 72, as by hinge 74 (FIG. 5) is a transverse member or frame 75 swingable from a position lying along the underside of seat member 72 to an unfolded position depending therefrom with its lower edge 76 adjacent bottom panels 1, 2. In such unfolded position frame 75 extends in a gene-rally vertical plane transversely of the boat with its vertical side edges adjacent side panels 3, 4.

.A latch means is provided which prevents the side panels 3, 4 from spreading when the transverse member '75 is in the unfolded position (FIG. 5 A slotted element 9, secured to each side panel is adapted to receive a tongue 8 secured to each edge of member 75 when "said member is moved into the unfolded position. This engagement of tongues 8 in the slots in elements 9 prevents spreading of the side panels 3, 4.

Frame 75 is held in said unfolded position 'by releasable latch means 77 which provide a pair of opposed flanges 78, 79 adapted to receive lower'edge 76 therebetween. Latch means 77 is secured to keel construction 14 and one of said flanges 78, 79 is mounted for movement away from the lower edge 76 of frame 75, preferably as by mounting it on a hinge leaf 80. By swinging hinge leaf 80 and flange 79 oppositely away from the latched position shown in FIG. 5, frame 75 may be swung upwardly and removed with seat member 72 in the manner described.

When frame 75 is in the unfolded, downwardly depending position, flanges 78, 79 embrace the lower edge 76 thereof and securely hold it in place. It is advantageous to form hinge leaf 80 to a slightly bowed, spring construction whereby flanges 78, 79 will yieldably engage the opposite sides of frame 75 at its lower edge. The remaining portions of the lower edge of each frame 75 may be formed to a contour corresponding to the desired contour of bottom panels 1, 2 (FIG. 2) so that frames '75 assist in forming said bottom panels to the bowed configuration described against their inherent resiliency.

In folding the boat of this invention from its set-up condition shown in FIGS. 1 and 2, the frames 75 are first unlatched and swung to a generally horizontal position and then the seat members 72 removed by springing side panels 3, 4 outwardly to permit removal of the ends of the seat members from sockets 73. The next step is the disassembly and collapsing of transom panel 6 and includes removing through bolt 46, collapsing transom brace 47, as described, and removing outer panel 36 from angle members 44. The thwarts 7 and outer panel 36 are the only structural members which are separate and independent from the remainder of the boat.

in further folding the boat of this invention the inner rear panels 34, 35 are then folded oppositely into overlying relation with the side panels 3, 4 to which they are hingedly connected. Said side panels with rear panels 34, 35 adjacent thereto are then folded oppositely inward- 1y on their respective bottom panels 1, 2. Flexible rear end member 37 is then pulled rearwardly out of the way and deck member 68 tucked inwardly while bottom panels 1, 2 are folded upwardly and together with side panels 3, 4 and rear panels 34, 35 folded therebetween.

The boat of this invention may thus be folded to a compact unit for transporting or storage purposes. When folded the boat of this invention occupies a space of approximately six inches by 24 inches by the length of the boat. In a matter of minutes one man can unfold the boat of this invention and set it up in the condition shown in FIG. 2 ready for use. When in the unfolded condition this boat is sufliciently strong and braced to Withstand considerable rough usage and the carrying of substantial loads while remaining completely watertight.

Although the improved boat has been herein described in some detail, such is not to be taken as restrictive thereof since modifications which would occur to one skilled in the art are intended to be within the spirit and scope of the invention.

I claim:

1. In a foldable boat, a pair of elongated bottom panels, hinge means connecting said panels along their adjacent longitudinal side edges and including rigid means holding said side edges in spaced relation, said hinge means spanning the space between said side edges upwardly of the lower surfaces of said panels when the same are unfolded for providing an unobstructed, downwardly opening groove extending longitudinally centrally of the bottom of said boat.

2. In combination with a foldable boat having a pair of elongated bottom panels flexibly connected along their adjacent longitudinal side edges, a keel member, comprising: an elongated inverted channel having a web and downwardly depending legs extending along said side edges and disposed with said web positioned upwardly of the lower surfaces of said bottom panels when the same are in unfolded position thereby providing a downwardly 10 opening elongated groove along the central bottom of said boat.

'3. In combination with a foldable boat having a pair of elongated bottom panels flexibly connected along their adjacent longitudinal side edges, a keel member, comprising: an elongated inverted channel having a web and downwardly depending legs extending along said side edges and disposed with said web positioned upwardly of the lower surfaces of said bottom panels when the same are in unfolded position thereby providing a downwardly opening elongated groove along the central bottom of said boat, said channel extending from the rear end of said panels forwardly and opening rearwardly of the stern of said boat.

4. In combination with a foldable boat having a pair of elongated bottom panels and flexible connecting means connecting said panels along their adjacent longitudinal side edges, a keel member, comprising: an elongated in verted channel member having a central web, a pair of spaced downwardly depending legs, and a pair of oppositely outwardly extending flanges at the lower edges of said legs, and means securing said channel to said connecting means with said side edges of said bottom panels in unfolded condition respectively received in the outwardly and upwardly opening angles formed by said legs and said flanges thereby providing a downwardly opening longitudinal groove in the central bottom of said boat.

5. In combination with a foldable boat having a pair of elongated bottom panels and flexible connecting means connecting said panels along their adjacent longitudinal side edges, a keel member, comprising: an elongated inverted channel member having a central web, a pair of spaced downwardly depending legs, and a pair of oppositely outwardly extending flanges at the lower edges of said legs, and means securing said channel to said connecting means with said side edges of said bottom panels in unfolded condition respectively received in the outwardly and upwardly opening angles formed by said legs and said flanges thereby providing a downwardly opening longitudinal groove in the central bottom of said boat, said channel extending from the stern of said boat to approximately midship.

6. In a folding boat, a pair of elongated panels at least one of which is a bottom panel, a flexible strip secured in watertight relation to the adjacent longitudinal side edges of said panels for hingedly connecting the same, a flexible rear end member, means securing the peripheral edges of said member in watertight relation to the rear end edges of said panels adjoining said side edges for extending across and enclosing the stern of the boat when said panels are in unfolded condition, and the rear end portion of said strip being joined in watertight relation to said member for forming a watertight joint between said panels and said member.

7. In a folding boat, a pair of elongated panels at least one of which is a bottom panel, a flexible strip secured in watertight relation to the adjacent longitudinal side edges of said panels for hingedly connecting the same, a flexible rear end member, means securing the peripheral edges of said member in watertight relation to the rear end edges of said panels adjoining said side edges for extending across and enclosing the stern of the boat when said panels are in unfolded condition, said member having a projecting ear portion adjacent said side edges of said panels, and the rear end portion of said strip being enfolded with said ear portion into a watertight joint.

8. In a folding boat having a pair of elongated bottom panels, a flexible keel strip connecting said panels in watertight relation along their adjacent longitudinal side edges, a pair of elongated side panels, flexible chine strips respectively connecting said bottom panels and said side panels in watertight relation along the oppositely outwardly disposed edges of said bottom panels and the respective lower longitudinal edges of said side panels, and a flexible member enclosing the stern of the boat and having its peripheral edges secured in watertight relation to the rear end edges of said bottom panels and said side panels, watertight corner joint construction comprising: at the junctures between said side panels, said bottom panels and said member, an ear portion formed on said member and projecting from said peripheral edge, a rearwardly projecting tail portion formed in continuation of the adjacent said strip and interfolded with said ear portion, and means securing said ear portion and said tail portion in said interfolded condition.

9. In a folding boat having a pair of elongated bottom panels, a flexible keel strip connecting said panels in watertight relation along their adjacent longitudinal side edges, a pair of elongated side panels, flexible chine strips respectively connecting said bottom panels and said side panels in watertight relation along the oppositely outwardly disposed edges of said bottom panels and the respective lower longitudinal edges of said side panels, and a flexible member enclosing the stern of the boat and having its peripheral edges secured in watertight relation to the rear end edges of said bottom panels and said side panels, watertight corner joint construction comprising: at the junctures between said side panels, said bottom panels and said member an ear portion formed on said member and projecting from said peripheral edge, a rearwardly projecting tail portion formed in continuation of the adjacent said strip, said ear portion and said tail portion being rolled together with said tail portion on the outside of the roll thus formed, and means holding said ear portion and said tail portion in flattened, rolled condition.

10. In a folding boat, a pair of elongated panels at least one of which is a bottom panel, a flexible strip secured in watertight relation to the adjacent longitudinal side edges of said panels for hingedly connecting the same, a flexible rear end member, means securing the peripheral edges of said member in watertight relation to the rear end edges of said panels adjoining said side edges for extending across and enclosing the stern of the boat when said panels are in unfolded condition, said member having a projecting ear portion adjacent said side edges of said panels, said strip being secured to said panels in a manner to provide an inverted generally U-shaped cross section and having its rear end portion folded forwardly on itself and then rearwardly to provide a rearwardly projecting, upright, generally flattened U-shaped tail portion underlying said ear portion, and said portions being rolled together with said tail portion on the outside of the roll thus formed thereby providing a watertight joint between said panels and said member.

11. A folding boat comprising: a pair of elongated bottom panels flexibly connected along their adjacent inner longitudinal side edges for folding on each other and when unfolded extending forwardly and upwardly from the stern of the boat to the bow, said bottom panels having a convex shape and being oppositely upwardly and outwardly inclined to form a pointed bow, an elongated side panel flexibly connected along its lower longitudinal side edge to the outer longitudinal side edge of each .said bottom panel for folding thereon and when unfolded extending generally upright from the stern to its forward end short of the bow, said side panels being convexly outwardly curved and oppositely upwardly and outwardly inclined near said forward ends, thwarts extending transversely between Said panels for holding the same in unfolded codition, and a flexible deck member permanently secured to the upper free edges of said bottom panels forwardly of said forward ends of said side panels and extending over the bow, said deck member being taut when said panels are held in unfolded condition for preventing spreading of said bottom and side panels.

12. A folding boat comprising: a pair of elongated bottom panels, an elongated keel member, means flexibly connecting the adjacent inner longitudinal side edges of said bottom panels to said keel member for folding on each other and for forming the generaly horizontal bottom of the boat when unfolded, an elongated side panel flexibly connected along its lower longitudinal side edge of each said bottom panel for folding thereon and for forming the generally upright sides of the boat when unfolded, a transom panel, means for connecting said transom panel to the rear end edges of said side and bottom panels for enclosing the stern of the boat, an elongated base member secured to and extending along said keel member forwardly from the stern, an elongated upright member swingably connected to the rear end of said base member for swinging from a collapsed position extending along said base member to a raised position lying alongside said transom panel for bracing the same, an inclined member swingably connected to said base member at a point forward of its said rear end for swinging from a collapsed position extending along said base member to a bracing position extending into engagement with said upright member, and releasable means for securing said upright member and said inclined member to said transom panel.

13. A folding boat comprising: a pair of elongated bottom panels, an elongated keel member, means flexibly connecting the adjacent inner longitudinal side edges of said bottom panels to said keel member for folding on each other and for forming the generally horizontal bottom of the boat when unfolded, an elongated side panel flexibly connected along its lower longitudinal side edge of each said bottom panel for folding thereon and for forming the generally upright sides of the boat when unfolded, a transom panel, means for connecting said transom panel to the rear end edges of said side and bottom panels for enclosing the stern of the boat, an elongated base member secured to and extending along said keel member forwardly from the stern, an elongated upright member swingably connected to the rear end of said base member for swinging from a collapsed position extending along said base member to a raised position lying alonside said transom panel for bracing the same, an inclined member swingably connected to said base member at a point forward of its said rear end for swinging from a collapsed position extending along said base member to a bracing position extending into engagement with said upright member, and releasable means for securing said upright member and said inclined member to said transom panel, said transom panel being formed from a plurality of superposed separate sheets, and said releasable means extending across and clamping together said sheets, said upright member and said inclined member.

1-4. A folding boat comprising: a pair of elongated bottom panels, an elongated keel member, means flexibly connecting the adjacent inner longitudinal side edges of said bottom panels to said keel member for folding on each other and for forming the generally horizontal bottom of the boat when unfolded, an elongated side panel flexibly connected along its lower longitudinal side edge of each said bottom panel for folding thereon and for forming the generally upright sides of the boat when unfolded, a transom panel, means for connecting said transom panel to the rear end edges of said side and bottom panels for enclosing the stern of the boat, an elongated base member secured to and extending along said keel member forwardly from the stern, an elongated upright member swingably connected to the rear end of said base member for swinging from a collapsed position extending along said base member to a raised position lying alongside said transom panel for bracing the same, an inclined member swingably connected to said base member at a point forward of its said rear end for swinging from a collapsed position extending along said base member to a bracing position extending into engagement with said upright member, and releasable means for securing said upright member and said inclined member to said transom panel, said transom panel being formed from a plurality of superposed separate sheets, a rigid bearing plate extending transversely of said transom panel and superassays;

13 posed over the upper central portion thereof interiorly of the boat, and said releasable means including a bolt extending through said sheets, said plate and said upright and inclined members and threaded to receive a nut for clamping the same together.

15. A folding boat comprising: a pair of elongated bottom panels flexibly connected along their adjacent inner longitudinal side edges for folding on each other and when unfolded extending forwardly and upwardly from the stern of the boat to the bow, said bottom panels having a convex shape and being oppositely upwardly and outwardly inclined to form a pointed bow, an elongated side panel flexibly connected along its lower longitudinal side edge to the outer longitudinal side edge of each said bottom panel for folding thereon and when unfolded extending generally upright from the stern to its forward end short of the bow, said side panels being convexly outwardly curved and oppositely upwardly and outwardly inclined near said forward ends, a transom panel, means for connecting said transom panel to the rear ends of said side and bottom panels for enclosing the stern of the boat, oppositely inwardly opening sockets provided on said side panels intermediate their said ends, an elongated thwart adapted to extend transversely of the boat with its ends received in said sockets and having a length suiflcient to spread said side panels in unfolded condition against their inherent resiliency, and a frame swingably connected to said thwart for swinging to an unfolded position depending therefrom with its lower edge adjacent said bottom panels, and means releasably securing said frame in said unfolded position, said means including a pair of opposed flanges connected with said bottom panels and adapted to receive said lower edge of said frame therebetween, at least one of said flanges being mounted for movement away from said lower edge of said frame to permit swinging of said frame away from said unfolded position.

References Cited in the file of this patent UNITED STATES PATENTS 352,420 Martin Nov. 9, 1886 1,760,673 Van Hoorn May 27, 1930 1,861,048 Conover May 31, 1932 2,353,013 Clark July 4, 1944 2,408,579 Randrup Oct. 1, 1946 2,504,225 Randrup Apr. 18, 1950 

